Generally, in order to satisfy service quality requirements from a mobile station, a radio base station for public communications is operated as follows by a network operator in a mobile communication system.
(1) A private line is used as a line between radio base stations for public communications and a mobile telecommunications operator network, and traffic uncontrollable by the mobile telecommunications operator is not accommodated therein.
(2) Policies on priorities on data pieces flowing in the mobile telecommunications operator network are unified into one, and each of the data pieces is assigned a corresponding one of the priorities according to a service quality requirement by a user.
Note that such a radio base station, installed in a small-scale area such as a home, that is referred to as a “home radio base station (Home eNB), is assumed to be operated by being connected to a general access line, such as FTTH or ADSL, to which the user subscribes.